Smokers with gene defect have 25% risk of developing lung cancer

A quarter of smokers with a defect in the BRCA2 gene will develop lung cancer during their lifetime, suggests a new study published in Nature Genetics.

Around ten million adults smoke in the UK, which means that 200,000 could have the defect, know as BRCA2 c.9976T.

The defect - already known for its role in breast cancer - increases the risk of contracting lung cancer by around 1.8 times.

In general, smokers already have a heightened risk of developing the disease - 16 per cent in men and 9.5 per cent in women - but the study suggests around one in four of those carrying the defect will go on to contract it.

The DNA of 11,348 Europeans with the disease was compared to 15,861 without.

Professor Paul Workman, co-author of the study, said: ""These findings indicate that around a quarter of smokers with a specific defect in their BRCA2 gene will develop lung cancer – a disease which is almost invariably fatal.

“All smokers are taking a considerable risk with their health, regardless of their genetic profile, but the odds are stacked even more heavily against those with this genetic defect who smoke."